


Nighttide

by Saki101



Series: Other Experiments [28]
Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: Alternate Reality, Alternate Universe, M/M, Science Fiction, Slash
Language: English
Status: Completed
Published: 2012-07-27
Updated: 2012-07-27
Packaged: 2017-11-10 20:51:16
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,245
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/470554
Author URL: https://archiveofourown.org/users/Saki101/pseuds/Saki101
Summary: <blockquote class="userstuff">
              <p>With both Sherlock and John working on the experiment, the answers may come faster.</p><p>~~~~~~</p><p>Excerpt:  “Where have you gone?” The words were a deep murmur by John’s ear.  Sherlock’s fingers smoothed down John’s back, under the sheet, adding a slight ripple to the image in the narrow rectangle of glass.  John turned his eyes away from it, tilted his head up and pressed his lips to the vibration in the long throat.</p><p>“Mind reading?” he whispered back, against the skin, eyes closed.</p><p>“I can tell when your focus isn’t on me.  Always have done; it doesn’t take mind reading.” Sherlock turned his head, found the image floating in front of the leather-bound books.  “Ah,"...</p>
            </blockquote>





	Nighttide

**Author's Note:**

> This is a continuation of the [Other Experiments Series](http://archiveofourown.org/series/15644) which forms an AU frame for the _Experiments Series_ which begins with [Zygomata](http://archiveofourown.org/works/331460). _Nighttide_ follows [There Are Times When the Stars Are Too Close](http://archiveofourown.org/works/465364).

The sheet was barely moving. John glimpsed the faint outline in the glass doors of the bookcases covering the wall by the door. They should both be asleep. John knew that better than Sherlock, of course. He was supposed to be the sensible one about eating and sleeping, tending to the demands of the body. Yes, well. There were other demands, too long untended...as far as he knew anyway. John could have cast such an image for other reasons in the drear months now past, the lonely contours of a man who hadn’t adjusted to the absence of the body that brought him peace. Afterwards, tears had sometimes come. He had tried to be quiet, so Mrs Hudson wouldn’t hear if she were out in the hall. At those times, the sheet covering him would barely move at all.

“Where have you gone?” The words were a deep murmur by John’s ear. Sherlock’s fingers smoothed down John’s back, under the sheet, adding a slight ripple to the image in the narrow rectangle of glass. John turned his eyes away from it, tilted his head up and pressed his lips to the vibration in the long throat.

“Mind reading?” he whispered back, against the skin, eyes closed.

“I can tell when your focus isn’t on me. Always have done; it doesn’t take mind reading.” Sherlock turned his head, found the image floating in front of the leather-bound books. “Ah,” he said and drew his hand back up to John’s face, held it lightly beneath John’s jaw, feeling the pulse. The new skin on the tips of his fingers was very sensitive. John pressed his lips against Sherlock’s neck again, moved his hips ever so slightly.

Sherlock murmured as the image undulated. He skimmed his hand down once more to the dip and the swell, where it stopped. John’s hips rolled. Sherlock felt the muscles move beneath his hand and his eyes closed to savour John’s focus returning solely to him. “I might not want you to stop that,” Sherlock said.

“I don’t want to stop,” John said, his movement hardly more than the tensing of muscles. “I may fall asleep like this.” 

“Sleep, then,” Sherlock said. His hand slid into the small of John’s back and pressed downwards. John’s breath gusted over Sherlock’s throat and Sherlock pressed harder.

“You’re going to be sore as it is,” John murmured. “As your physician, I should be mindful.”

“Don’t stop,” Sherlock replied, tightening his muscles around John. John’s breath puffed hot against Sherlock’s skin.

“Sherlock,” John said and his voice drew out the syllables.

Sherlock feathered his hand along John’s back, the edges of his nails grazing the skin. In the glass, Sherlock watched the small wave roll along the sheet.

*** 

John was strewn diagonally across Sherlock when he awoke. Fingers were drumming against his shoulder. “You’re awake,” John mumbled. He thought to move, but coordination hadn’t yet returned to his limbs.

“For quite a while,” Sherlock replied, one fingertip running against the grain of the hair at the nape of John’s neck.

John took a full breath, felt the sheet caught between them restrict his movement. “And you didn’t tip me onto the floor? I’m flattered.” It was warm on top of Sherlock. Not too hot. _No fever._ Warm and solid. _Definitely here. No dream. No hallucination._

“I’ve formulated questions,” Sherlock said. 

“I’ve got plenty of those. May take us a good while to get through them.”

Sherlock’s hand smoothed along John’s shoulders and down one arm, lightly squeezing the biceps and moving on.

“If you keep doing that, I might not get up after all,” John said. “I could just carry on from where we were before we slept.”

“Could you?” Sherlock asked and he turned his hand so his thumbnail dragged across John’s skin.

“Christ,” John said and lifted his head. Sherlock’s eyes met his, dark and bright. “Was one of your questions how long I could keep going?” 

Sherlock blinked. “No. But we can add it to the list.”

John glanced at the fruit on the night stand. “Maybe a trip to the loo and then we could eat some of that, you know, for strength.” He raised himself on one arm and Sherlock slipped off the bed. 

John watched the motion. Sherlock met John’s eyes and smiled. John collapsed on the mattress and looked back. 

Sherlock did a survey of John from brow to toes and came back to John’s eyes. “Coming?” Sherlock asked and turned towards the door to the bath.

John tracked Sherlock’s progress across the room. _Steady._ When Sherlock had half-disappeared into the bath, John disentangled himself from the sheet and followed. _I always follow. Don’t forget to _let_ me follow._

*** 

“Describe it, as precisely as you can,” Sherlock said. “Move or sit as you did, re-enact it. It will help you remember.”

John glanced up from the shelves. Sherlock took a step back. The alcove didn’t afford much room to pace with the two of them in it, but Sherlock’s body clearly wanted to release energy in that familiar way. “Yes. All right,” John said. He brushed past Sherlock to remove a few bound manuscripts, drew out a box file from behind them, checked the label. “This,” he said and slid down to the floor. “I was sitting, leafing through this.” John paused. “The handwriting, you know…” He stopped speaking, turned pages. “There. This one,” John said and when he looked up Sherlock’s face seemed too far away. 

Sherlock crouched down, noted the paper upon which John’s hand rested, the way his fingertip was moving over the dried splash mark. 

“I imagined you drinking tea while you were revising it, a drop falling here.” John’s finger was rubbing across the mark more noticeably. “It made him real, this you of years ago. I pictured you researching here where I was, too…probably.” John sighed. “The date’s not clear.” His finger moved, traced the letters and numbers that were still legible. “There's a sense of you, of what I’d missed then, what I missed now.” 

Sherlock heard the change in time sense, narrowed his eyes.

“The anger's too strong, boiling over. It’s hot. I need air.” 

Sherlock could see the sheen spreading across John’s forehead, observed how John was leaving his mouth open to breath. 

“Mike said the stairs go up to doors to the outside balcony. I climb them and the city sparkles, but there’s not enough air.” John looked back at the paper, his palm flat against it, pressing hard. “The hatred is spreading. It feels infinite.” John took a deep breath. “I feel faint.” 

Sherlock sat down next to John, lifted John’s hand and took the file away. “I rearranged the papers a few months ago,” Sherlock said. He tapped the spot. “It wasn’t tea.”

*** 

“How nearby?” John asked, his voice rising to a harsh whisper. They spoke quietly in the library, a habit so well-ingrained it seemed almost an instinct.

Sherlock turned from looking down into the reading room, tilted his head towards the open fresco panel. “One night I was standing there.” 

John put his hand up to his forehead. 

“I watched you, waited for you to get thirsty, drink the water…sleep. I wanted you.” 

John’s hand dropped. “Christ.” 

Sherlock raised his arm, hand open, let it fall back to his side.

“No, Sherlock.” John stepped closer. “No, I walked away from you in the graveyard. I did it again in the lab. I’m done walking away.” John’s hands closed around both of Sherlock’s arms, fingers digging into the muscles. 

Sherlock kept his eyes on John’s face. 

“I meant it when I said I forgive you everything.” John exhaled slowly. “Doesn’t mean I’ve forgotten though,” he said, glancing down into the reading room. His voice dropped. “I felt close to you here…I should remember…” He looked back up at Sherlock’s face, “…everything I felt about missing you.” Sherlock’s muscles shifted beneath John’s hands.

“There are other things I’m going to tell you, John,” Sherlock said.

John inclined his head towards the reading room. “I might need to remember those feelings then, yeah?”

Sherlock nodded.

*** 

John leaned his elbows on the lab table as Sherlock increased the magnification. “You never tested this before?” John asked.

Sherlock smiled at the incredulity in John’s voice. “Of course I did, long ago. Mycroft’s, too. It was similar,” Sherlock replied.

“Mycroft let you?” 

“We were young. The chemistry set was a birthday gift. Blood type was a logical first thing to test,” Sherlock said. “My lab notes are in the archives.” 

“I can’t picture him letting you draw blood. How old was he?” John asked, leafing again through the pages of results they had so far.

“Oh, he used the lancets on us both. I only needed a couple drops. He was twelve. I quite looked up to him then.”

“You got a chemistry set for your fifth birthday? From whom?” 

“My mother thought it would engage me. And when I say chemistry set, I mean lab equipment from Bart’s.” 

“Right,” John said, watching how still Sherlock sat. “Your mother wasn’t wrong. So, way back then you saw that your blood, and Mycroft’s, I presume, was unusual.” 

“Well, O negative isn’t the rarest blood type,” Sherlock replied. “That rather disappointed me at the time. But the morphology didn’t match anything in the manual. We got out our grandfather’s haematology texts next. Nothing like it there either.” 

“A mutation, then, inherited from one of your parents?”

“The idea had occurred. Couldn’t confirm it though,” Sherlock murmured, making a quick notation. “Our father was rarely in England and our mother always managed to distract me when I asked for a blood sample. She was good at distracting me when I was a child.”

“Self-defence,” John said.

The corner of Sherlock’s lip lifted. Sherlock slipped the slide he was examining out and took another from the rack. “It was my grandfather who finally sat me on his knee one day in his office and explained the facts of life, as it were.” 

“How old were you?”

“Five and a half,” Sherlock replied.

“Yes, well, that would have been a long time for _you_ to wait. But weren’t you rather young?” 

“To learn about procreation?” Sherlock asked, lifting an eyebrow. “I already knew the various ways terrestrial creatures propagate.”

“Excuse me,” John said as his eyes swept over Sherlock’s face, pictured Sherlock fresh from a shower, hair slicked back…descending from the roof. John supposed that image was never going to leave him. 

“Not aquatic or avian. Not terrestrial in the broader sense. It wasn’t an earthly phenotype. Well, not completely.”

John thought of bright night skies and the longing they always inspired. How overpowering it sometimes was.

Sherlock turned to John, reached out with a fingertip and touched the small needle mark on John’s forearm. “And now neither are you.” John stared. Sherlock slipped off the stool and gestured for John to have a seat and look.

 

John’s body moved, his mind occupied with Sherlock’s statement, considering its implications.

John scowled as he scrutinised the slide. His hand twisted the knob to increase the magnification. Somewhere to his left, he heard the tinkle of slides touching and then he tuned even that out. The cells were all mildly distorted. _No wonder you never wanted to go to a hospital, Sherlock._ In the upper righthand corner of the slide, a cluster of neutrophils John recognised as his own, were swarming around a cell that looked liked the biological material they had identified as Moriarty’s. There was a small twinge of satisfaction, but the process didn’t hold John’s attention. He continued scanning until he found one of his white blood cells splitting around one of Sherlock’s erythrocytes, each half nudging against the red blood cell’s wall until both pierced it. 

“Sherlock?” John said quietly.

He had observed something analogous in his own blood, where Sherlock’s cells were merging with various cells of his, not just the erythrocytes, but Sherlock’s cells had been haploid already. He had noted no other cell type of Sherlock’s in his blood or Mike’s or Molly’s or Mrs Hudson’s, although it had only been in his blood that he had witnessed Sherlock’s cells merging with host cells.

John drew in a breath. He had spotted another of his white blood cells dividing, becoming haploid. In this instance, two of Sherlock's erythrocytes were close to one another. First, one half of John’s halved white blood cell entered one of Sherlock’s cells, then the other half succeeded with the second of Sherlock’s cells. Their cell walls appeared to close behind the fragment of John’s white blood cell once it cleared the membrane. John’s eyes shifted back to the first cell which combined his and Sherlock’s cellular material. It was splitting in half.

“Sherlock,” John whispered. He felt Sherlock’s hand on his shoulder.

“Interesting?” Sherlock asked.

“How do you interpret the activity of my white blood cells?” John asked, unable to take his eyes away from the microscope.

“I believe, since they have eliminated almost all of Moriarty’s biological material, they are now propagating,” Sherlock replied.

“Diploid cells don’t do that,” John said. “Gametes do that.” John observed two of his white cells divide around one of Sherlock’s erythrocytes and all four halves pierce its cell membrane. The resultant cell split almost immediately. “There are all different combinations.” John altered the magnification, let out a long breath. “My cells did not do this in Molly’s blood, not to her cells or to yours.” John noted a cluster where four of Sherlock’s red blood cells had surrounded one of his leukocytes. His white blood cell split in half and then the halves divided, each quarter entering one of the erythrocytes. John let out a long breath. “They’re so...active.” 

“Your cells?”

“Mm,” John murmured, not shifting his eyes.

“If they hadn’t been, what Moriarty had planned to do to me would probably have succeeded,” Sherlock said. John glanced up at that. “It seems the process proceeded more rapidly in my system than yours. And it’s not just in the blood.” Sherlock ripped open a sterile cotton swab packet. “I’ll prepare a slide,” he said and swiped the swab along the inside of his cheek.

“When did you…?”

“After I saw you in the cemetery, the fever returned,” Sherlock said. “When it subsided, I tested everything I could.”

“Mike came to see me. Said there was something going around among the med students. Took blood,” John recalled, his eyebrows rising. “My fever was mild.”

“As I said,” Sherlock replied.

John followed the preparations, the precise movements of the fingers he thought lay mouldering under the sod. _Did I ever really believe that? I feared it, but there was always that stubborn hope that kept me from believing it._ “I was out in the open, Sherlock, you couldn’t have been close,” John eventually said. “Airborne in a room, in a crowd outside maybe, but…what kind of range are we talking about?” 

“Think how far away you were up on the balcony. In the cemetery, it was about a hundred fifty metres,” Sherlock said, replacing the slide in John’s microscope.

“You couldn’t have heard me, then,” John said.

“Microphone. Base of the headstone,” Sherlock replied.

John dragged his hands down his face, head tilted up towards the ceiling. “OK,” he said. “I was addressing _you_. Guess it’s good you actually heard me.” John looked back at Sherlock.

Sherlock's shoulders hunched over the microscope. John placed a hand in the middle of Sherlock’s back, watched the shoulders begin to straighten. 

“We can go through the old records. You can see how minimal and vague they are for yourself. Perhaps you can help me spot something in them I’ve not noticed,” Sherlock said, straightening up completely and tapping the base of the microscope. He avoided John’s eyes. “Compare this one.”

John swivelled around on the stool and looked. 

*** 

John slid off the ottoman to stretch out on the floor, his back resting against the old leather. Sherlock glanced up at the movement. John kept reading.

“These early entries read more like poetry than any sort of a record,” John said after he’d turned another couple pages. “Is it code?” He looked over the book at Sherlock.

“If it is, I haven’t been able to crack it. I have most of it memorised, I’ve read it so often,” Sherlock replied.

“How could something incorporeal alter genetic material?” John asked. Sherlock raised an eyebrow. “All right. Radiation can alter genetic material.” John subsided, reached up for the plate of sliced pears and cheddar sitting on the night table. He held it out to Sherlock who shook his head. John set the plate on the carpet and took a slice. The pears were ripe; he fumbled for a serviette. Sherlock saw a drop land on John’s shirt before he wiped his chin dry. “What would it be like to be a moonbeam?” John said.

Sherlock waited. John’s leaps of logic, or illogic, were often useful.

“What’s the weather like? Is it clear? What’s the moon phase?” John sat up straighter. “I have this odd inclination to lay down on one of the reading tables out there or, better yet, on the floor of the top balcony and consider the moon.” Sherlock picked his mobile off the carpet. “If it’s visible tonight,” John added.

“Visibility is better in the country,” Sherlock said, scrolling through pages on his phone. “Waxing gibbous. Partly cloudy. Ten percent chance of rain.”

John got up on his knees. “Your relative out there,” John began, his hand waving at the door to the office. “He’s one of the original ones?” Sherlock nodded. “And not as many great, greats as Mike said?”

“It’s a painting of my grandfather as a young man,” Sherlock replied.

John looked steadily at Sherlock. “Not fancy dress?” Sherlock shook his head. “Were you cloned?”

“No, an actual conception and birth,” Sherlock replied.

“You’re sure?”

“Mycroft says he remembers the birth, at home. And Dr Bertrand was the attending physician,” Sherlock added.

“It doesn't confirm the conception. You could be twins,” John said, looking carefully at Sherlock. “I spent a lot of time admiring that portrait.”

Sherlock looked down at the book in his lap for a moment. When he looked back up, John had moved closer. “Imagine,” John said, reaching out and touching Sherlock’s cheek. “Imagine how a moonbeam would feel touching your cheek.” Sherlock’s brows drew together. “How its light would make your skin seem even paler,” John murmured, stroking down to Sherlock’s jaw with the back of his fingers. “How it would resent the clothes and the shadows that hid your skin from it.” John’s hand moved down Sherlock’s neck and under the open collar.

“John?” Sherlock said.

John shuffled closer on his knees, bent forward and touched his lips to Sherlock’s for an instant. “It would want to feel the warmth inside here,” John murmured and touched his lips more firmly against Sherlock’s.

Sherlock drew back. “John!”

John sat back on his heels, his hands settling on his thighs. “I don’t think those are notes or code,” John said and his eyes flitted over Sherlock’s face, along his neck and back to his eyes. “They’re love letters to someone who murmured words of longing to a blazing night sky.” John glanced upwards, his hand lifting slightly off his leg. “And something travelling between the stars heard them and changed course.”


End file.
